The conservative opposition in Croatia is leading in vote-counting from the country's parliamentary elections, held amid economic woes and a massive migrant surge.

With about 50 percent of the vote tallied, the conservatives, led by former intelligence chief Tomislav Karamarko, won 60 seats in the 151-seat parliament, while Social Democrats, led by incumbent Prime Minister Zoran Milanovic, had 53.

The partial results suggest neither bloc has won an outright majority in the November 8 polls, and will depend on several small parties to form a new government.

Milanovic called on Most, the newly formed group of citizens without clear political stands, to start talks on a new coalition.

"Croatia has decided for a change," Milanovic said. "We cannot do it alone."

Analysts say a return to power by Croatia's conservatives could impact the flow of migrants crossing the small country.

Since September, Croatia has seen an influx of more than 330,000 people fleeing war and poverty and seeking a better life in wealthier EU states such as Germany.

The conservatives have criticized Milanovic's government for allowing a free flow of migrants and have hinted they would build fences and deploy the army to the border to stop the flow.

"Our election campaign was very passionate. Unfortunately, it has been marked by the migrant crisis as well as by hate speech and hate mongering of the [conservative] backers," Milanovic said as he cast his ballot.

His ruling coalition, which campaigned with the slogan "Croatia Is Growing," has repeatedly accused the opposition of corruption.

Croatia remains one of the poorest-performing economies in the EU, and the government had been blamed for failing to enact reforms to its public sector or improve the country’s business climate over the past four years.

Unemployment stood at 16.2 percent in September -- 43.1 percent among young people -- while public debt stands at nearly 90 percent of Croatia’s gross domestic product.

The vote represented a revival for Karamarko's conservative Croatian Democratic Union party, which led Croatia during its war for independence from the Serb-led Yugoslavia in the 1990s and then dominated its political scene for years. Its popularity plummeted after a series of corruption trials against top officials.

The presidential election victory earlier this year of a conservative, Kolinda Grabar-Kitarovic, was a clear sign that Croatia is shifting to the right after the center-left bloc's four-year rule.

Karamarko campaigned on patriotism and creating new jobs, while Milanovic promised economic revival and warned against allowing Croatia to return to its conservative past.